> Refueling nuclear aircraft carriers have projections start to finish, a half decade long.
The difference is that those projections weren't spit out on the fly by a engineer after a 15 minute pitch of some manager's great new idea. Those plans took many months of effort to put together by a team of specialists planning out the various details of the project. Software does have the equivalent of this, it's called waterfall development. The reason we don't do this is because, unlike aircraft carrier design, if you take six months to create a project plan your requirements will have likely already substantially changed.
The difference is that those projections weren't spit out on the fly by a engineer after a 15 minute pitch of some manager's great new idea. Those plans took many months of effort to put together by a team of specialists planning out the various details of the project. Software does have the equivalent of this, it's called waterfall development. The reason we don't do this is because, unlike aircraft carrier design, if you take six months to create a project plan your requirements will have likely already substantially changed.